Hardware-in-the-Loop-Tests von elektrischen Fahrzeugantrieben
- Hardware-in-the-loop tests of electric traction drives
Etzold, Konstantin; Andert, Jakob Lukas (Thesis advisor); Abel, Dirk (Thesis advisor)
Aachen : RWTH Aachen University (2022)
Dissertation / PhD Thesis
Dissertation, Rheinisch-Westfälische Technische Hochschule Aachen, 2022
In order to reduce automotive development investments in cost and time for integration, calibration and validation of electric powertrains, particular development tasks are rescheduled to earlier program phases which is usually referred to as frontloading. For frontloading, prototype vehicle tests are shifted to component test benches (road2rig approach). For multiple validation tasks it is crucial that the device under test e.g. an electric drive is tested considering all interactions with neighboring vehicle components. In this contribution, a hardware-in-the-loop methodology is presented with focus on how these interactions can be replicated at component test benches with closed-loop real-time simulations and how electric drives can be calibrated and validated within a virtual vehicle. The hardware-in-the-loop setup is described as cascaded control system considering a multiple input multiple output system. Thereto, the mathematical equations of the multiple input multiple output systems are derived and the cross couplings are analyzed. Due to this analysis, the inner control circuits are set up as decentralized control, which is calibrated considering stability and high dynamics. For the outer control circuits, the simulation models of a battery electric vehicle are developed based on particular measurement data. The device under test consists of an electric drive with a permanent magnet synchronous machine and an inverter. The electric drive is set up at a laboratory test bench and connected with the simulation models to a hardware-in-the-loop setup. The hardware-in-the-loop setup is analyzed considering reproducibility and successfully validated by means of vehicle measurements performed on a chassis dynamometer. Thereafter, parameter variations are conducted for a high load test cycle (Nürburgring Nordschleife) as well as for the Worldwide Harmonized Light Vehicle Test Cycle (WLTC). Based on these parameter variations the significant influence of the interactions between the electric drive and the simulated vehicle components on the driving performance are demonstrated. Finally, an exemplary feasibility study for frontloading of the calibration of electric drives is conducted. Thereto, the driving functions for thermal derating, recuperation and a virtual high voltage dc-dc converter are optimized in terms of available power and energy efficiency as well as successfully validated. These use cases demonstrate the potential of hardware-in-the-loop setups in order to test and optimize electric drives in interaction with the entire vehicle in early phases of automotive development programs.